CAUSE
One question. One truth.
“Why is Pluto not a planet anymore?”
Pluto's reclassification as a dwarf planet stems directly from the International Astronomical Union's 2006 definition, which requires a planet to clear its orbital neighborhood—a criterion Pluto fails because it shares its orbit with Kuiper Belt objects.
Medium confidenceStructural
CURRENT STATE
Currently, Pluto is officially classified as a dwarf planet under the IAU's criteria. It orbits the Sun and is nearly round but lacks orbital dominance. This status is widely accepted in the astronomical community and textbooks worldwide as of December 5, 2025.
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